MX2007013221A - Methods and apparatus of downhole fluid analysis. - Google Patents

Abstract

Methods and apparatus for downhole analysis of formation fluids by isolating the fluids from the formation and/or borehole in a pressure and volume control unit that is integrated with a flowline of a fluid analysis module and determining fluid characteristics of the isolated fluids. Parameters of interest may be derived for formation fluids in a static state and undesirable formation fluids may be drained and replaced with formation fluids that are suitable for downhole characterization or surface sample extraction. Isolated formation fluids may be circulated in a loop of the flowline for phase behavior characterization. Real-time analysis of the fluids may be performed at or near downhole conditions.

Description

METHODS AND APPARATUS FOR THE ANAUSE OF THE I FLUIDS LOCATED IN THE FUND OF THE DRILLING WELLS DATA OF THE RELATED APPLICATION The present application claims priority under Document 35 U.S.C. § 120 as a partial continuation of the Non - Provisional Application of the United States! idos, Serial No. 10/908161 (Attorney's Reference No. 20.2974) that names D. Freemark et al., as the inventors, and assigned on April 29, 2005, in the pending present, the aforementioned application is incorporated here in its entirety, as reference and for all purposes.

FIELD OF THE INVENTION I The present invention relates to the field of analysis of fluids located at the bottom of drilling wells of a geological formation, to evaluate and test the formation for the purposes of exploration and development of hydrocarbon production wells, like gas or oil wells. More particularly, the present invention is directed to suitable methods and apparatuses for isolating the fluids from formation and for characterizing the isolated fluids which are located at the bottom of the well.

BACKGROUND OF THE INVENTION The analysis of fluids located at the bottom of a drilling well is an important and efficient technique typically used to determine the characteristics and nature of the geological formations that have deposits of hydrocarbons. In this, the typical explorations and developments of the oil fields include the analysis of the fluids located at the bottom of the drilling wells, to determine the petro-physical and fluid properties of the reservoirs of the hydrocarbons. The characterization of the fluids is integral together with an accurate evaluation of the economic viability of the formation of the reservoirs of hydrocarbons. i Typically, a complex mixture of fluids, such as oil, gas and water, are found in the reservoir formations located at the bottoms of the wells. The fluids located at the bottom of the wells, which are also referred to as formation fluids, have characteristics, including pressure, temperature, volume, among other properties of the fluids, which determine the behavior of the phase of the various constituent elements of fluids. For the purpose of evaluating the underground formations surrounding the wellbore, it is often desirable to obtain samples of the formation fluids that are located in the wellbore, for the purposes of characterizing the fluids, including the analysis of the composition, the properties of the fluid and the behavior of the phase. Well line tools for the testing of formations are discussed, for example, in U.S. Patent Nos. 3,780,575 and 3,859,851, and the Reservoir Formation Tester ( PFR) and Schlumberger Modular Formation Dynamics Tester (PMDF) are examples of sampling tools for the extraction of fluid samples from formations, from the hole in a well, for analysis in the surface.

The fluids of the formation, under the conditions prevailing in the hole of the well, in relation to composition, pressure and temperature, are typically different from the conditions of the fluids, under the conditions prevailing in the surface, for example, the localized temperatures in a well they could vary from 300 degrees Fahrenheit. When samples of fluids located at the bottom of the well are transported to the surface, there is a tendency for a change in the temperature of the fluids to occur, with concurrent changes in volume and pressure. Changes in fluids, as a result of their transportation to the surface, can cause phase separation between the gaseous and liquid phases in the samples, and changes in the characteristics of the fluid compositions of the formation.

There are also known techniques for maintaining the pressure and temperature of samples taken from a well, in order to obtain samples on the surface that are representative of the fluids of the formation located at the bottom of the well. In conventional systems, samples taken from the bottom of the well are stored in a special chamber of the formation tester and the samples are transported to the surface to be analyzed in the laboratory. During the transfer of the sample from the sub-surface to a laboratory located on the surface, the samples are often transferred from a sample bottle or container to another bottle or container, as a transport tank. In this, the samples could be damaged during the transfer from one container to another.

Additionally, the pressure and temperature of the sample change frequently during the transport of the samples, from the site of a well to a remote location laboratory, despite the techniques used for the maintenance of the conditions existing in the hole of the well , of the samples. The transfer of samples and transport procedures that are currently used, are notorious for damaging or damaging the fluid samples of the formation by the formation of bubbles, by the precipitation of solids in the sample, among other difficulties associated with the handling of the fluids of the formation, for the effects of its analysis on the surface in reference to the characteristics of the fluids.

Additionally, laboratory analyzes performed at a remote site, consume time. The provision of the data obtained from the analysis of the samples, take from a couple of weeks to months for them to perform the comprehensive analysis, which obstructs the ability to meet the demand of users of products that offer real-time responses . Typically, the time frame required to respond to the products related to surface analysis for formation fluids is a few months after the samples have been sent to a remote location laboratory. I As a consequence of the disadvantages that occur in the conduct of the analyzes on the surface, of the fluids of the formation, the recent events within the industry, in relation to the procedures of analysis of the fluids located at the bottom of the well , include techniques to characterize formation fluids located at the bottom of a drilling well. In this, the PMDF could include one or more fluid analysis modules, such as the Fluid Composition Analyzer (ACF) and the Fluid Current Analyzer (AAF) from Schlumberger, for example, to analyze the fluids tested by the tool and located at the bottom of the well, while the fluids are still at the bottom of the well.

In the analysis modules of the fluids located at the bottom of the well, such as those previously described, the fluids of the formation that are to be analyzed in the bottom of the well, flow beyond a sensor module associated with the analysis module of fluids, such as a spectrometer module, which analyzes fluids flowing through infrared absorption spectrography, for example. In this, an optical fluid analyzer (AOF), which can be? located in the fluid analysis module, it could identify the fluids in the flow stream and be able to quantify the oil and water content. U.S. Patent No. 4,994,671 (hereby incorporated by reference in its entirety) discloses an apparatus located in the hole of the well having a test chamber, a light source, a spectral detector, a database , and a processor. Fluids removed from the formation and directed into the test chamber are analyzed by directing the light to the fluids, detecting the spectrum of the transmitted and / or scattered light, and processing the information (based on the information it is found in the database and that it is available for different spectra), with the purpose of characterizing the fluids and the formation.

Additionally, U.S. Patent Nos. 5,167,149 and 5,201,220 (both incorporated herein by reference in their entirety) describe apparatus for estimating the amount of gas present in a fluid stream. A prism is attached to a window located in a stream of fluids and light is directed through the prism, to the window. The light reflected from the in-face of the fluid / window flow at certain specific angles is detected and analyzed to indicate the presence of gas in the flow of the fluids. As it has been established in U.S. Patent No. 5,266,800 (incorporated herein in its entirety, by reference), monitoring the optical deposition spectrum of the fluid samples obtained over a period of time could allow a person to be able to determine when it is that the fluids of the formation, instead of the filtered ones of mud, are flowing towards the module of analysis of fluids. Additionally, as described in U.S. Patent No. 5,331,156 (incorporated herein in its entirety, by reference) when making optical density (OD) measurements of fluid flow to certain pre-determined levels of energy, the fractions of oil and water of a two-phase fluid stream, could be I quantified.

On the other hand, samples taken from the bottom of the well are analyzed in a laboratory located on the surface, through the use of a pressure and volume control unit (UCPV) that is operated at room temperature and heated the fluid samples to that of the formation conditions. In this, a UCPV that is able to operate with precision to the conditions of high temperatures of the formation, has not been available. The conventional type apparatus for changing the volume of fluid samples that are under the prevailing conditions at the bottom of the well, use the hydraulic pressure with a concurrent disadvantage, which is the difficulty of being able to accurately control the race and the piston velocity under the prevailing conditions at the bottom of the well, due to the expansion of oil and COMPENDIUM OF THE INVENTION i As a consequence of the previously discussed background, and of other factors that are known in the field of the analysis of the fluids located at the bottom of the well, the applicants have discovered methods and apparatus for the analysis of the fluids of the formation, by means of of the insulation of the formation fluid and / or the hole of the well, in a flow line of a fluid analysis module. In the preferred embodiments of the invention, the fluids are isolated with a pressure and volume control unit (UCPV) which is integrated with the flow line, and the characteristics of the isolated fluids are determined using, in part, the UCPV.

Advantageously, the UCPV is suitable for the applications to be made erji the bottom of the well, and because the flow line and / or the UCPV of the tool | located at the bottom of the well are used to isolate the formation fluids, the unwanted fluids of the formation can be easily drained and replaced with the formation fluids that are suitable for the characterization of the bottom of the well. Another advantageous result obtained by isolating the fluids from the formation in accordance with the present invention is that the analysis of the pressure-volume-temperature (PVT) relationship of the fluids located at the bottom of the well can be performed at or near of the prevailing conditions at the bottom of the well and using the UCPV of the present invention.

Applicants recognize that there is a need for bottomhole analysis, which provides accurate response products in conjunction with sampling, by means of a tool located at the bottom of the well, such as a test tool Of the information.

Applicants have also recognized that fluid analysis of bottomhole well formation, which is reliable and comparable in its field of action with laboratory-based analyzes, addresses the known problems of destruction of soil samples. the fluids of the formation, due to its transportation to the surface.

Applicants have additionally recognized that the analysis performed at the bottom of the well, obviates a delay involved in the transfer of the samples of the fluids from the formation, to a laboratory located on the surface, by providing products that offer real-time answers, at the well site.

The applicants have discovered that the characterization of the fluids made in the fluids that are isolated from a hole formation or well, in order to be in relative stability, the static state will tend to be more precise compared to the analysis of the fluids located at the bottom of the well that are in an active flow state, while they are being characterized.

Applicants have recognized that a sample of fluid isolated in the flow line of a tool, compared to a sample of fluid captured in a sampling chamber of a tool located at the bottom of the well, has advantageous benefits because the fluid isolated can be verified in its quality and can be replaced with another insulated fluid of better quality, based on the initial fluid quality not be suitable for I the characterization of the fluid. In this, it is possible to drain a flow line from a fluid analysis module and extract the fresh fluid from the formation for analysis, while the tool is at the bottom of the well and at where the sampling chambers are located. conventional type and containers, may not have the means for draining the fluid being sampled and that acquires another sample of the formation fluids, while the tool is located at the bottom of the well.

The Applicants have recognized that having an insulated fluid located at the bottom of the well, under conditions that are substantially similar to the conditions prevailing in the formation or in the hole of the well, provides unexpected advantages in carrying out the characterization of the fluid, due to that tests such as the determination of the bubble point require less time under the conditions at the bottom of the well, as compared to the laboratory environment located on the surface.

In the preferred embodiments of the methods and apparatuses of the present invention, a suitable tool to be used at the bottom of the well, isolates (the fluids from the formation of the formation or from the hole of the well, in a line d Tool flow Advantageously, the tool flow line could include a pressure and volume control unit (UCPV) that is integrated with the flow line, so that changes in pressure and The volume of the fluids isolated from the formation is possible under the conditions existing at the bottom of the well The fluids isolated from the formation can be analyzed by means of the measurement of the properties of the fluid, such as its composition, the Gas-oil ratio (RGP), BTU, density, viscosity, compressibility, determine the phase behavior of fluids, such as the initial pressure of the asphaltene, the bubbling point, the saturation point n; ^ measure the fluid pressure and the temperature values.

In an embodiment of the present invention, an apparatus for analyzing the fluid located at the bottom of the well has a plurality of devices, such as, for example, sealing valves, which can be selectively operated to stop and initiate the flow of the fluids. of the formation, in at least portions of the flow line and in one or more of the sensors associated with a flow line of the apparatus. In a preferred embodiment of the invention, a UCPV includes a pump, such as a syringe-type pump, which is operatively connected to the flow line, so that the characteristics of the fluids isolated from the formation in the UCPV can be varied , through. variation of the volume of the fluids.

In a preferred embodiment of the present invention, the formation fluid is retained or isolated in the flow line, by operation of the valves; sealing. Advantageously, the characteristics of the insulated fluid can be determined. In one aspect of the invention, an optical sensor, for example, can measure the properties of interest of the fluid, such as the composition of the hydrocarbon, the RGP and the BTU of the fluid isolated from the formation. As another aspect of the invention, a suitable device, such as a density and viscosity sensor, could measure additional fluid properties of interest, such as the density and viscosity of the fluid. As yet another aspect of the invention, a pressure / temperature sensor (P / T meter) will be able to measure the temperature! and the fluid pressure of the fluid isolated from the formation.

Advantageously, the UCPV could change the fluid pressure by expanding the volume of the fluid isolated from the formation located within the flow line: In yet another aspect of the invention, the compressibility of the fluid could be measured with the volume changed and with the pressure changed, or the change in fluid density or optical absorption level could be determined.

In yet another aspect of the present invention, the pressure of the fluid and the isolated formation fluid can be reduced to a certain pressure, so that the asphaltene is precipitated. Advantageously, optical sensors, for example, could be used to detect precipitation of asphaltene. An additional increase in pressure could cause the gaseous components to separate from the liquid phase. An ultrasonic sensor and optical sensors, for example, could be used to detect the leakage of gas bubbles.

If the insulated fluid is a gas condensate, when the fluid is under a certain pressure, the condensed oil could escape from the gas condensate. For example, up optical sensor could be used to detect oil condensed. The properties of the time-dependent sensors can be monitored to detect the segregation of the severity of the phases. After completing the measurements of interest, the sample of the isolated fluid could be drained to become mud, the fresh fluid from the formation could be withdrawn to the flow line to uncover the flow line, and a sample of the The formation could be captured in a suitable chamber or container of the sample of the tool located at the bottom of the well, to be transported to the surface to be analyzed in the laboratory.

In accordance with the invention, a fluid analysis module of a downhole fluid characterization device includes a flow line for the formation fluids to flow through the analysis module; fluid. At least one selectively operable device, such as a valve and / or pump in the preferred embodiments of the invention, may be provided to isolate a quantity of the fluids in the flow line. At least one sensor is located in the flow line to measure the i parameters of interest that are related to the fluids in the flow line.

In the preferred embodiments of the invention, a first and a second selectively operable device comprises a valve. In other embodiments of the invention, a selectively operable device comprises a pump, for example, in a pump module, and the other comprises a valve. Preferably, a pump unit, such as a syringe-type pump, integrated with the flow line, is provided for various volume pressure levels of the isolated fluids.

Unio more sensors, such as a spectral sensor optimally coupled to the flow line; a fluorescence and gas sensor; a density sensor; a pressure sensor; a temperature sensor; a gas / bubble sensor; a sensor based on MEM; an image producer; a resistivity sensor; a chemical sensor; and a dispersion sensor, are provided with respect to the flow line for the characterization of formation fluids in the flow line. In the preferred embodiments of the invention, a bifurcation flow line is provided and the selectively operable devices are structured and arranged to isolate the fluids in the bifurcation flow line.

A circulation line interconnects a first end of the bifurcation flow line with a second end of the bifurcation flow line, so that the isolated fluids can be circulated in the circulation line and in the bifurcation flow line. , by means of a circulation pump.

In a preferred embodiment of the invention, one or more amounts of a spectral detector optimally coupled to the flow line; a fluorescence and gas detector; a chemical sensor; and a resistivity sensor are provided in the flow line for the measurement of the parameters of interest that relate to the fluids flowing through the flow line and towards one or more density sensors; a pressure gauge; a temperature meter; a gas / bubble detector; a sensor based on MEM; an image producer; and a dispersion detector system are provided to measure the parameters of interest that relate to the isolated fluids in the bifurcation flow line.

The present invention provides a method for downhole characterization of formation fluids using a tool located in the bottom of the well having a fluid analysis module with a flow line. The method includes monitoring at least one first parameter of interest that | it is related to the formation fluids that flow in the flow line; when a pre-determined criterion for the first parameter of interest is satisfied, the flow of formation fluids in the flow line is restricted, by means of the operation of a plurality of devices selectively operable to isolate the fluids from the formation, in a portion of the flow line of the fluid analysis module; and characterizing the isolated fluids by means of the operation of one or more sensors located in the flow line.

Other preferred embodiments of the method include characterization of the isolated fluids to determine one or more fluid properties of the isolated fluids including, in a preferred embodiment, by changing the fluid pressure of the isolated fluids as the volume varies of the isolated fluids before determining the property or properties of the fluid, for example, one or more fluid compressibilities; the beginning of asphalt precipitation; bubble point; and saturation point. Another preferred embodiment of the method includes circulating the isolated fluids in a closed circuit of the flow line, while characterizing the fluids isolated, for example, by determining the phase behavior of the isolated fluids. Advantageously, the properties of the sensor dependent on time can be? monitored to detect the segregation of the severity of the phases.

Yet another embodiment of the present invention provides a tool | for the characterization of formation fluids, located at the bottom of the well in a reservoir of an oil field. A method for the analysis of a tool fluid includes a flow line for the formation fluids to flow through a bifurcation flow line and a line interconnecting a first end of the flow line. bifurcation with a second end of the bifurcation flow line that is provided, so that the fluids located in the flow line can be circulated by means of a circulation pump. At least one sensor is located in the bifurcation flow line to measure the parameters of interest that are related to the fluids located in the bifurcation flow line.

Additional advantages and novel features of the invention will be established in the description that follows or that can be learned by those trained in the art, through reading the materials contained herein or through the practice of the invention. The advantages of the invention could be achieved through the means recited in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings illustrate the preferred embodiments of the present invention, and which are part of the specification. In conjunction with the following description, the drawings demonstrate and explain the principles of the present invention.

FIGURE 1 is a schematic representation in cross section of an exemplary operating environment of the present invention.

FIGURE 2, is a schematic representation of an embodiment of a system for carrying out downhole analysis of the formation fluids, in accordance with the present invention, with an exemplary tool of the cable tool, deployed in a drilling well.

FIGURE 3 schematically shows a preferred embodiment of the cable tool according to the present invention, with a fluid analysis module, having a pressure and volume control unit! (UCPV) for the analysis of the bottom of the well, of the fluids of the formation.

FIGURE 4 shows, in schematic representation, an embodiment of a fluid analysis module, with a UCPV apparatus in accordance with the present invention, for the downhole characterization of fluids, by means of isolation of the fluids of the formation.

FIGURE 5 is a schematic exposition of a UCPV apparatus, with a sensor arrangement in a fluid analysis module in accordance with an embodiment of the present invention.

FIGURE 6 is a schematic representation of a dispersed detector system of the UCPV apparatus in accordance with an embodiment of the present invention.

FIGURE 7 represents, in a flow chart, a method according to the present invention for the characterization of formation fluids.

FIGURE 8 graphically depicts compressibility measurements of a fluid sample in accordance with an embodiment of the present invention.

FIGURE 9 shows a schematic representation of another embodiment of an apparatus according to the present invention, for the characterization of the fluids located at the bottom of the well.

FIGURE 10 shows, in schematic representation, yet another embodiment of an apparatus in accordance with the present invention, for the characterization of fluids located at the bottom of the well.

Throughout the drawings, identical reference numbers indicate similar but not necessarily identical elements. While the invention is susceptible to being subjected to various modifications and alternative forms, the specific embodiments have been shown by way of example in the drawings, and will be described here in detail. However, it should be understood that the invention is not intended to be limited to the particular forms set forth. Instead, the invention must cover all modifications, equivalents and alternatives that fall within the scope of the invention, as defined by the appended claims.

DETAILED DESCRIPTION OF THE PREFERRED INCORPORATIONS Illustrative embodiments and aspects of the invention are described below. In the interest of clarity, not all the characteristics of a current implementation are described in the specification. Of course, it will be appreciated that in the development of any of a current incorporation, numerous implementations and specific decisions must be made to achieve the specific goals of the developer, such as the limitations related to the system and the limitations related to the business. , which may vary from one implementation to another. Moreover, it will be appreciated that such a development effort could be complex and time-consuming, but would otherwise be a routine task for those with ordinary training in | art and that have the benefit of what is exposed here.

The present invention is applicable to the exploration and development of oil fields in areas such as the analysis of the fluid located at the bottom of the well, using one or more fluid analysis modules in the Tester.

Modulate the Formation Dynamics (PMDF) of Schlumberger's, such as: FIGURE 1 is a schematic cross-sectional representation of an exemplary operating environment of the present invention, wherein a service vehicle 10 is located at the well site having a well hole or a borehole 12, with a tool located in the well hole 20 that is suspended there, at the end of a cable line 22. FIGURE 1, exposes a possible adjustment for the use of the present invention and other operating environments are also contemplated herein invention. or example, it should be understood that instead of being deployed in a tool located on the cable line, the method and the inventive apparatus could be deployed on a slippery line, on a monitoring collar during drilling, on a pipe in spiral, or as part of a construction team, permanent or semi-permanent. Typically, the wellbore 12 contains a combination of fluids such as water, mud filtrate, formation fluids, etc. The tool of the well hole 20 and the cable line 22 are typically structured and arranged with respect to the service vehicle 10, as shown schematically in FIGURE 1, in an exemplary arrangement.

FIGURE 2, is an exemplary embodiment of a system 14 for analysis and sampling of the fluids of the downhole formation, in accordance with the present invention, for example, while the service vehicle 10 is located at the well site (see FIGURE 1). In FIGURE 2, a wellbore system 14 includes a well hole tool wire 20, which could be used for the testing of land formations and for analyzing the composition of the formation fluids. The wellbore tool 20 is typically suspended in the wellbore hole 12 (also see FIGURE 1) from the lower end of a multi-conductor monitoring cable, or from the cable line 22 that is | coiled on a crane 16 (note again FIGURE 1) located on the surface of the formation. The monitoring cable 22 is typically electrically coupled to an electrical control system located on the surface 24, which has appropriate electronic systems and processing systems for the tool located in the hole of the well 20. i Referring also to FIGURE 3, the tool located in the opening of the hole 20 includes an elongate body 26 enclosing a variety of components and electronic modules, which are schematically represented in FIGURES 2 and 3, to provide the necessary and desirable functionality to the tool cable located in the hole of the well 20. A selectively extensible fluid that admits the assembly 28, and an extensible member of the anchoring tool 30 (see FIGURE 2) are respectively disposed on opposite sides of the elongate body 26. The fluid intake assembly 28 is operable to selectively seal or isolate selected pol- lutions from a hole wall of a well 12, so that pressure or fluid communication with the adjacent terrestrial formation is established. The fluid intake assembly 28 could be a single test module 29 (shown in FIGURE 3) and / or a packaging module 31 (also schematically shown in FIGURE 3). Examples of tools located in the wellbore are disclosed in the aforementioned US Patents Nos. 3,780,575 and 3,859,851, and in United States Patent No. 4,860,581, the contents of which are incorporated herein by reference. they are incorporated here in their entirety, as a reference.

One or more fluid analysis modules 32 are provided in the body of the tool 26. The fluids obtained from a formation and / or from the hole of a well, fluyer through a flow line 33, via a module or of fluid release modules 32, and then they can be discharged through a port of a pumping module 38 (see Figure 3). Alternatively, the formation fluids in the flow line 33 can be directed to one or more fluid collector chambers 34 and 36, such as the 1, 23M, or 6-gallon sample chambers and / or six modules of multiple samples of 450 cubic centimeters, for the reception and retention of the fluids obtained from the formation, for transport to the surface.

The fluid intake assemblies, one or more fluid analogue modules, the flow path and the collector chambers, and other operational elements of the tool cable located in the hole of the well 20, are controlled by means of control systems. electrical control, such as the electric control system located on the surface 24 (see FIGURE 2). Preferably, the electric control system 24, and other control systems located in the tool body 26, for example, include processing capabilities for characterizing the fluids of the formation in the tool! 20, as described in more detail below.

The system 14 of the present invention, in its various embodiments, preferably includes a control processor 40 operatively connected to the tool cable from the hole of the well 20. The control processor The control signals up to the operating elements of the hole 20 gel hole tool cable.

The computer program can be stored in a storage medium usable by a computer 42 associated with the processor 40, or it could be stored in an external storage medium usable by a computer 44 and electronically coupled to a processor 40 to be used. according to the requirements. The storage medium 44 could be any of one or more of the currently known storage media, such as magnetic disks that fit a disk drive, or Operable in a CD ROM reader, or in reading devices of any other type, including a remote storage device coupled over an activated telecommunication link, or in future storage media suitable for the purposes and objectives described herein.

In the preferred embodiments of the present invention, the methods and apparatus discussed herein can be incorporated into one or more fluid analysis modules of the Schlumberger training tester tool, The Tested? Modular of the Dynamics of the Formations (PMDF). The present invention provides, advantageously, a formation test tool, such as PMDF, with improved functionality for the characterization of the formation located in the hole of the well and for the collection of the samples flowed from the formation. In this, the training tool could be advantageously used for the sampling of the formation fluids in conjunction with the characterization of the formation fluids.

FIGURE 4 is a schematic exposition of a preferred embodiment of the fluid analysis module 32, with a pressure and volume control unit (UCPV) 70 (see also FIGURE 3). In the preferred embodiments of the present invention, the UCPV apparatus 70 could be integrated with the flow line 33 of the module 32. One or more sensors 11 (one of the sensors is schematically shown in FIGURE 4, for the purposes of of illustration) and operable devices 52 and 54 (from now on in advance also generically referred to as "valves") to activate and deactivate the flow of fluids, are operatively associated with the flow line 33. For example, as shown in FIGURE 4, devices 52 and 54 could be sealing valves having an electrically operated feed motor, with an associated piston arrangement for open and close the valve. In this, the selectively operable devices 52 and 54 could be any suitable flow control device, such as a pump, a valve, or other type of mechanical and / or electrical device, to activate and stop the flow of the fluids in the flow line 33. One or more of the devices 52 and 54 could be located in the fluid analysis module 32, or they could be located in other modules adjacent to the tool 20, such as the pump module 38 ( see FIGURE 3). Moreover, combinations of devices could be used as necessary or desired, for the practice of the present invention.

The UCPV apparatus 70 includes a pump 71, such as a syringe type pump. The pump 71 controls the volume of the formation fluids in the flow line 33, between the valves 52 and 54. The pump 71 has a direct current pulse motor 73; 79 ball screw; a piston and sleeve arrangement 80 bon an O-ring (not shown); the ball screw coupling with the motor 93; the ball screw bearings 77; and a block 75 connecting the ball screw 79 with the piston 80. Advantageously, the UCPV apparatus 70 and the pump 71 are operable at high temperatures of up to 200 ° C. The section of the flow line 33 with the intake valve (for example, the valve 52 is shown in FIGURE 4) is directly connected to the pump 71 to reduce the static volume of the fluid isolated from the formation. In this, by placing the piston 80 of the pump 71 along the same axial direction as that of the intake segment of the flow line 33, the static volume of the insulated fluids is reduced due to the volume of the fluids Remaining in the flow line 33 of the previously sampled fluids, affects the properties of the fluids of the fluids sub sampled.

The flow line 33 can be branched in two directions, with a branch! connected to the outlet valve (valve 54 in FIGURE 4) and the other connected to a pressure / temperature meter 64 to receive information about the pressure / temperature characteristics of the fluids of the formation in the flow line 33. In the embodiment shown in FIGURE 4, the pump 71 has, for example, an electric current / pulse motor 73 with a gear to reduce the vibration effect, a ball screw 79, a piston arrangement. and sleeve 80, and a linear position sensor 82, such as a potentiometer. For the purpose of reducing vibrations, a 1/160 reduction gear could be used and to precisely control the position of the piston 80, an electric current advance motor with a 1.8 degree pulse could be used. The axis of the piston 80 could be off center relative to the axis of the bolt 79 and with the motor 73, so that the overall length of the tool is minimized.

During its operation, the rotational movement of the motor 73 is transferred to the axial displacement of the piston 80, through the ball screw 79, with a guide key 91. The changes in the volume can be determined by the displacement value of the piston 80, which could be directly measured by an electrical potentiometer 82, for example, while accurately and changeably controlling the rotation of the motor 73, with a pulse of 1.8 degrees, as an example. He! direct current electric pulse motor 73 can change the volume of the formation fluids retained in the flow line, by means of the activation of the piston 80, connected to the motor 73, by means of electric control mechanisms using sensors of position signal. Because the preferred embodiment of the invention includes a pulse motor and a high resolution position sensor, the operation of the UCPV can be controlled with a high level of accuracy. The change in volume is calculated by a surface area of the piston multiplied by the displacement distance recorded by a displacement sensor or by a linear position sensor, such as a potentiometer, which is operatively connected to the piston. During the change of volume, various sensors, such as pressure, temperature, chemical and density sensors, could measure the properties of the fluid sample captured between two sealing valves 52 and 54.

When it is determined that the formation fluids satisfying predetermined criteria are flowing in the flow line 33, the two sealing valves 52 and 54 are closed to capture the formation fluids in the UCPV 70, under the prevailing conditions at the bottom of the well. The electric motor 73 could be activated to change the volume of the position sensor 82, fixed by way of a nut seal 95 and a block 75, with the piston 80, while pulses are sent to the motor 73 to precisely control the speed of displacement and piston distance 80. The UCPV 70 is configured based on the desired performance of the motor, required by the conditions at the bottom of the well, the operating time, the reducer and the circumference of the ball screw. After the measurements of the characterization of the fluid are completed by the sensors and by the measuring devices of the module 32, the piston 80 is returned to its initial position and the sealing valves 52 and 54 are opened, so that the UCPV 70 is ready for another operation.

FIGURE 5 schematically depicts a preferred embodiment of a pressure and volume control unit (UCPV) 70 having a sensor array disposed in the fluid analysis module 32 in accordance with the present invention. As shown in FIGURE 2, the module 32 is in fluid communication, via the flow line 33, with a formation that surrounds a well hole 12. Referring again to FIGURE 5, in an embodiment preferred, the UCPV apparatus 70 has, for example, two sealing valves 52 and 54 operatively associated with the flow line 33. The valves 52 and 54 are located so as to control the flow of the formation fluids in a segment of the flow line 33 and for isolating the formation fluids in the segment of the flow line 33 located between the two valves 52 and 54. In accordance with the embodiments of the present invention, valves such as valves High pressure and high temperature suitable for use at the bottom of the wells, could be used to control the flow of the formation fluids in the flow line 33. For example, a sealant valve and regulator could be used in accordance with the present invention.

[One or more optical sensors, such as an optical spectrometer 56 with 36 channels, are connected by means of a group of optical fibers 57, with an optical cell or with a refractometer 60 and / or a fluorescence and gas detector 58, could be arranged in the flow line 33, to be located between the sealing valves 52 and 54. The optical sensors could, advantageously, be used to characterize the fluids flowing through or being retained in the flow line 33. U.S. Patent Nos. 5,331,156 and 6,476,384, and U.S. Patent Application Publication No. 2OO4 / OOOO6 6A1 (incorporated herein by reference in its entirety) disclose methods for characterizing the fluids of the formation.

A density sensor 62 and / or pressure / temperature sensors 64 could also be provided in the flow line 33, to acquire the density, pressure and / or temperature measurements, with respect to the fluids in the line segment. of flow 33 located between the sealing valves 52 and 54. In these viscosity and / or density sensors, such as X-ray sensors, gamma-ray sensors, wire sensors and vibrating cylinders, between others could be advantageously used for the characterization of the fluids, in accordance with the embodiments of the invention.

A resistivity sensor 74 and / or a chemical sensor 69 could also be provided in the flow line 33, to acquire the measurements of the fluid resistance of the fluids and / or to detect the CO2, H2S, pH, among others properties! Chemicals, with respect to the fluids in the flow line 33 located between the sealing valves 52 and 54. U.S. Patent No. 4,860,581, herein incorporated in its entirety by reference, discloses apparatus for the analysis of fluids, by means of measurements of electrical resistance and / or pressure in the fluid located at the bottom of the well.

An ultra sonic transducer 66 and / or a micro-fabricated and micro-electro-mechanical viscosity and density sensor 68 could also be provided to measure the characteristics of formation fluids, through or captured on the line. of flow 33 located between valves 52 and 54. U.S. Patent No. 6,758,090 and Patent Application Publication No. 2002 / 0194906a1 incorporated herein by reference in its entirety) disclose methods and apparatus to detect the fluid sensors based on the SMMEM and the pressure at the bubble point, respectively.

A dispersion detector system 76 could be provided in the flow line 33 to monitor the separation phase in the isolated fluids, by means of the detection of particles, such as those of asphaltene, bubbles, petroleum dew of the gas condensates, which are detached from the isolated fluids in the flow line 33. FIGURE 6, is a schematic representation of a dispersion detector system of apparatus 70, in accordance with an embodiment of the present invention. Advantageously, the dispersion detector 76 could be used to monitor the phase separation, by means of the detection of the bubble point, as graphically represented in the FIGURE. 6.

The scattering djector 76 includes a light source 84, a first photo-detector 86 and, optionally, a second photo-detector 88. The second photo-detector 88 could be used to evaluate the fluctuation in the intensity of the light source 84, to confirm that the variation or fall in intensity is due to the formation of bubbles or solid particles in the formation of fluids that are being examined. The light source 84 could be selected from a halogen source, from an LED, from a laser diode, among other known sources of light, for the purposes of the present invention.

The scattering detector 76 also includes a high-temperature, high-temperature sample cell 90 with windows, so that the light originating from the light source 84 passes through the forming fluids that flow through or that are located in the flow line 33, up to the photo-detector 86 located on the other side of the flow line 33, from the light source 84. Suitable collection optical devices 92 can be provided, between the light source 84 and the detector photo 86, so that the light originating from the light source 84 is collected and directed to the photo-detector 86. Optionally, an optical filter 94 could be provided between the optical means 92 and the photo-detector 86. In this, because the dispersion effect is dependent on the size of the particles, that is, a maximum for wavelengths similar to or less than those of the particle sizes, by means of the selection of the lengths With appropriate waves using the optical filter 94, it is possible to obtain adequate data about the sizes of the bubbles.

Referring again to FIGURE 5, a pump unit 71; such as a pumping unit per syringe, could be arranged with respect to the flow line 33, to control the volume and pressure of the fluids retained in the flow line 33, located between the valves 52 and 54. A system of video image 72, such as a CCD camera, could be provided in the flow line 33 to produce the spectral image to characterize the phase behavior of the fluids located at the bottom of the well, as set forth in the U.S. Patent Application No. 11 / 204,134, entitled "Spectral Image Production for the Characterization of the Fluids Located at the Bottom of a Well" concurrently assigned herein.

FIGURE 7, represents, in the form of a flow diagram, a preferred method according to the present invention for the analysis of the bottom of the well and for the sampling of the fluids of the formation, and for the generation of products of the answers of interest, based on the characterization of the fluids located at the bottom of the well. Referring also to FIGURES 2 and 3, when an operation of the fluid analysis module 32 is started (step 100 of FIGURE 7), the probe 28 is extended from the tool cable. 20 to make contact with the formation (observe FIGURE 2). The pump module 38 (see FIGURE 3) directs fluid from the formation to the flow line 33 (Step 102) and drains it into the mud. Module 32 analyzes the level of sample contamination and phase separation (Step 103) while the fluid is flowing into the flow line 33. The Patent of the United States No. 5,266,800, here incorporated in its entirety by reference, discloses methods for distinguishing between fluids containing mud-based oil and oil samples from the formation.

Referring also to FIGURES 4 and 5, after the contamination has reached a level which is determined to be sufficiently low for the purposes of characterizing the fluids and / or for the collection of samples, for example, contamination of the 0% to about 10%, and the fluid in the flow line 33 is confirmed as a single phase, the two sealing valves 5: 2 and 54 are closed so that the fluid of the formation is isolated or trapped in the flow line 33 located in the valves 52 and 54 (Step 104). The sensors and the meters of the apparatuses 32 could be operated for the measurements of the properties of the fluids, such as the density and viscosity of the fluids isolated from the formation in the flow line 33 (Step 105) and the pressure and the temperature (Step 106) of the fluid isolated from the formation.

The pump unit 71 could be operated to change the pressure of the insulated fluid in the flow line 33 (Step 108). The sensors of the apparatus 33 could be operated to monitor and record the compressibility of the fluid and the behavior of the phase of the isolated fluid, such as in the case of the beginning of the precipitation of the asphaltene, the point of bubbling, the point of saturation, among others (Steps 110 and 112).

The video image system 72, such as the CCD camera, could be used to monitor the precipitation of asphaltene, the initiation of bubbling, and the separation of liquid from the gas condensate. The image producer 72 could also be used to measure the change in the size of the asphaltene when the pressure of the isolated fluid is decreasing. The aforementioned, concurrently assigned, U.S. Patent Application No. 11 / 204,134, is directed to the production of spectral images for the characterization of fluids, all of whose contents are contained herein by reference.

After completing the measurements of interest, the sample of isolated fluid could be drained into the mud (Step 114). The fresh fluid from the formation could be directed towards the flow line, to clear the flow line (Step 116). A sample of the fluid from the formation could be captured in a suitable chamber or container! for samples of the tool located at the bottom of the well, for transport to the surface for laboratory analysis (Step 118).

FIGURE 8 graphically shows the compressibility measurement of a fluid sample. The compressibility of the fluid is calculated from the initial volume, the volume changed and the decrease in pressure. In this, the compressibility of the fluid retained in the flow line could be calculated from the decrease in pressure and the increase in the fluid volume derived from the displacement recorded by a displacement or position sensor, such as in the case of potentiometer 82 (previously described in connection with FIGURE 4).

FIGURE 9 schematically represents another preferred embodiment of a fluid analysis module 32 in accordance with the present invention. The apparatus 70, shown in FIGURE 9, includes a bifurcation flow line 35 and a circulation line 37 in communication with the fluid, via a main flow line 33, with a formation surrounding a well bore. In a preferred embodiment, the apparatus 70 of FIGURE 9 includes two sealing valves 53 and 55 operatively associated with the branch flow line 35.

The valves 53 and 55 are located so as to control the flow of formation fluids in the bifurcation segment of the flow line 35 of the main flow line 33, and to isolate the formation fluids. in the bifurcation flow line 35 located between the two valves 53 and 55. A valve 59 could be located in the main flow line 33 to control the flow of fluid in the main flow line 33.

One or more optical sensors, such as a 36-channel optical spectrometer 56, connected by a group of optical fibers 57 with an optical or refractive cell 60, and / or a fluorescence / refraction detector 58, could be arranged in the line of flow 35, to be located between valves 53 and 55. Optical sensors could be advantageously used to characterize the fluids flowing through or being retained in the bifurcation flow line 35.

A pressure / temperature meter 64 and / or a resistivity sensor 74 could also be provided in the bifurcation flow line 35 to acquire the electrical resistance of the fluid, the pressure and / or temperature measurements with respect to the fluids of the fluid. the bifurcation flow line 35 located between the sealing valves 53 and 55. A chemical sensor 69 could be provided to measure the characteristics of the fluids, such as the content of CO2, H2S, pH, among other chemical properties. An ultra sonic transducer 66 and / or a viscosity and density sensor 68 could also be provided to measure the characteristics of the fluids of the formation flowing through or captured in the bifurcation flow line located between the valves. 53 and 55. A pump unit 71 could be disposed with respect to the bifurcation flow line 35 to control the volume and pressure of the formation fluids retained in the bifurcation flow line 35, located between the lines 53 and 55. An image producer 72, such as a CCD camera, could be provided in the bifurcation flow line 35 to produce the spectral image to characterize the phase behavior of the isolated fluids located at the bottom of the hole.

A dispersion detector system 76 could be provided in the branch flow line 35 to detect particles, such as asphaltene, bubbles, | oil dew of the gas condensate, which are released from the insulated fluids in the branch flow line 35. A circulation pump 78, for example, a gear pump or a Sanchez pump, could be provided in the circulation line 37. Because the circulation line 37 is a circuit flow line of the branch flow line 35, the circulation pump 78 could be used to circulate the formation fluids which are isolated from the line of flow. bifurcation flow 35 in a circuit formed by the branch flow line 35 and in the circulation line 37.

In the embodiments of the invention set forth in FIGS. 4 and 5, after the formation fluid is isolated or trapped in the flow line 33, by the operation of the valves 52 and 54, the additional fluid flow of the formation in the flow line 33, is stopped. However, in some circumstances it may not be desirable to stop the flow of fluid in the main flow line 33, because if the valve located in the main flow line 33 is damaged, the work should be abandoned to replace the defective valve . To be able to address such possibilities, where stopping the flow of fluid in the main flow line 33 is not a preferred decision for characterization of the fluid, the branch flow line 35 of the embodiment of FIGURE 9 is provided, and the sensors and measuring devices of the fluid analysis module 32 will be located in the branch flow line 35. In the embodiment of FIGURE 9 of the invention, the fluid flow could be maintained in the main flow line 33. even after the formation fluid has been isolated in the bifurcation flow line 35. Alternatively, the valve 59 could Í regulate the flow of fluid in the main flow line 33.

The applicants have discovered that the accuracy of the phase behavior measurements are improved if the sample of the isolated fluid located in the line. { of branch flow 35 is circulated in a closed circuit line. Similarly, the bifurcation flow line 35 is closed circuit, via a circulation line 37, and the circulation pump 78 is provided in the closed circuit flow line 35 and 37, so that the fluids of the isolated formation in the bifurcation flow line 35 could be made circular, for example, during the characterization of the phase behavior.

FIGURE 10 schematically represents yet another preferred embodiment of a fluid analysis module 32 in accordance with the present invention. The apparatus 70 shown in FIGURE 10 is similar to that of the embodiment of FIGURE 9, with a bifurcation flow line 35 and with a circulation line 37 in fluid communication, via a main flow line 33, With a formation that surrounds the hole of a well. The apparatus 70 of FIGURE 10 includes two valves 53 and 55 operatively associated with the bifurcation flow line 35. The valves 53 and 55 are located so as to control the flow of formation fluids in the segment. from I the branching branch line 35 of the main flow line 33 and to isolate the formation fluids in the branch flow line 35, located between the two valves 53 and 55. A valve 59 could be located in the main flow line 33, in order to control the fluid flow located in the main flow line 33.

The abarato 70 shown in FIGURE 10 is similar to the apparatus shown in FIGURE 9, except that one or more optical sensors, such as a 36-channel optical spectrometer 56, connected by a group of optical fibers 57 with an optical cell or with a refractometer 60, and / or a fluorescence / refraction detector 58, could be arranged in the main flow line 33, in place of the main flow line 35, as shown in FIGURE 9. The optical sensors could be used to characterize the fluids flowing through the main flow line 33, because optical sensor measurements do not require an isolated and static fluid. Instead of the arrangement shown in FIGURE 9, a resistivity sensor 74 and a chemical sensor 69 could also be provided in the main flow line 33 in the embodiment of FIGURE 10, to acquire the electrical resistance of the fluid and the measurements chemical, with respect to the fluids that flow in the main flow line 33.

A temperature / pressure meter 64 could be provided in the branch flow line 35, for acquiring the pressure and / or temperature measurements with respect to the fluids in the branch flow line 35, located between the valves 53 and 55. An ultrasonic transducer 66 and / or a viscosity and density sensor! 68, could also be provided to measure the characteristics of I the fluids of the formation that flow through or captured in the bifurcation flow line 35 between the valves 53 and 55.

A pumping unit 71 could be disposed with respect to the branch flow line 35 to control the volume and pressure of the formation fluids retained in the branch flow line 35 between the valves 53 and 55. A producer of image 72, such as a CCD camera, could be provided in the bifurcation flow line 35, so that the spectral image producer can characterize the phase behavior of the isolated fluids located at the bottom of the well. A dispersion sensing system 76 could be provided in the branch flow line 35 to detect particles, such as asphaltene, bubbles, oil dew from the gas condensates, which can be detected by the gas stream. originate from the isolated fluids in the bifurcation flow line 35. Advantageously, a circulation pump 78 could be provided in the circulation line 7. Because the circulation line 37 is a flow line in circuit of the branch flow line 35, the circulation pump 78 could be used to circulate the formation fluids that are isolated in the flow line of the flow. branch 35, in a circuit formed by the bifurcation flow line 35 and the circulation line 37.

The ends of the flow line 33 extending from the fluid analysis module 32 could be connected to other modules in the training test tool, for example, with a CFA and / or an LFA. The fluids extracted from the formation and / or from the hole of the well, flow through the flow line for the analysis of the fluid at the bottom of the well, by means of interconnected modules. During the operation of the tool located at the bottom of the well 20, the valves of the apparatus 70 are usually open. The sensors and meters located in the flow line could be selectively operated to monitor the characteristics of the formation fluids that pass through the flow line.

Advantageously, the methods and apparatuses of the present invention have two approaches for the characterization of formation fluids. One, an analysis of the flowing fluid and, second, an analysis of the trapped or isolated fluid. In this, the data from the analysis of the flowing samples could be provided for the users on the surface, and could also be used to compensate for and / or validate the data of the isolated fluid analyzes.

When you are sure that a fluid flowing through the flow line is single-phase, that is, oil or water or gas formation without phase separation, and a level of fluid contamination is confirmed as not When the fluid is changed and is at a pre-determined level for the purposes of analyzing the fluid properties, valves 52 and 54 on the flow line 33 (see FIGURE 4 and 5) will be closed and a sample of the fluid will be isolated or trapped in the flow line. After the formation fluid is isolated in a segment of the flow line, the properties of the fluid, such as the composition, the RGP, and the BTU, can be measured by means of an optical spectrometer, for example. U.S. Patent Nos. 5,859,430 and 5,939,717, which are hereby incorporated by reference in their entirety, disclose methods and apparatus for determining the RGP and analyzing the composition.

A density nsor could measure the density of the fluid isolated from the formation. An SMMEM, for example, could measure density and / or viscosity, and a pressure / temperature meter could measure pressure and temperature. A chemical sensor could detect various chemical properties of the fluid isolated from The formation, such as those of CO2, H2S, pH, among other chemical properties.

A pump unit connected to the flow line could increase the volume of the sample isolated from the fluid, that is, the fluid pressure is reduced in the flow line. When the drop in pressure results in the phase transition, the time-dependent signals could be generated in the sensors as! gravity separates the phases, as further discussed in the Asphalt Precipitation from Crude Oil, Joshi, N.B. et al., Energy & Fuels 2001, 15, 979-986. In this, by means of monitoring the properties of the sensor in relation to the segregation of gravity over time, they could be detected.

In addition to the methods described above, the compressibility of the isolated fluid could also be measured by means of the use of a density sensor, an optical spectrometer and a pump. The fluid pressure could be additionally reduced, so that the phase behavior of the isolated fluid, such as the asphaltene, the bubble point, the saturation point, could be measured by means of a spectrometer, a detector fluorescence and gas, and an ultrasonic transducer.

In other preferred embodiments of the present invention, as shown in FIGURES 9 and 10, the fluid analysis module 32 could consist of a module in a series of interconnected modules of a formation test tool, such as the Schlumberger PMDF. When a work done at the bottom of the well is started using the tool! of formation test, a probe, such as probe 29 of FIGURE 3, is extended outwardly from tool 20 and attached to the formation (note assembly 28 in FIGURE 2). The tool 20 extracts the fluid from the formation, which passes into a pressure test chamber for the measurement of the pressure in the formation. After the pressure test is completed, the pump module 38 (see FIGURE 3) is operated to draw the formation fluid into the interior of the main flow line 33 (see FIGURES 9 and 9). 10) and to extract the fluid from the formation into the hole of the well, that is, into the mud surrounding the tool 20 located in the hole of the well. Sensors and devices located in the flow line, such as a spectrometer, a fluorescence detector, a resistivity sensor, and a D / V sensor, monitor changes in the level of contamination in the fluids of the formation that is find flowing in the flow line. When the fluid contamination levels of the formation reach a pre-determined level, and when the fluid phase is verified as a single phase, then the main valve of the flow line 59 of the module 32 (observe again the FIGURES 9 and 10) will be closed and the valves of the bifurcation flow line 53 and 55 will be open, so that the formation fluid flows into the bifurcation flow line 35 to replace the previous fluid in the branch flow line 35. The valves of branch flow line 53 and 55, are then closed and valve 59 located in branch flow line 33 is open, so that the formation fluid is isolated or trapped in the bifurcation flow line 35, located between valves 53 and 55.

After isolating the fluid from the formation in the bifurcation flow line 35, the characteristics of the fluid isolated from the formation, such as density, viscosity, chemical composition, pressure and temperature, could be measured. The circulation pump 78 (note again FIGS. 9 and 10) could be operated to circulate or mix the formation fluid in the bifurcation flow line 35. A pumping unit could be operated to increase the volume of the fluid isolated from the formation in the bifurcation flow line 35, so that the fluid pressure is reduced. A dispersion detector, an ultrasonic transducer, and / or a CCD camera could be used to measure the bubble point of the fluid isolated from the formation.

During the analysis of the pressure, volume, temperature (PVT) of the fluid isolated from the formation, or after the analysis of the PVT has been computed; a sample of the formation fluid could be captured in one or more sampling chambers, such as in 34 and in 36 in FIGURE 3, for surface analysis. Then the tool 20 could be moved to the next test point in the formation.

In conventional methods and apparatus, a sample of the formation fluid is collected at the bottom of the well and is then transported to a laboratory located on the surface for analysis. In this, typically a chamber or sampling vessel is necessary to maintain the pressure and temperature of the sample to that of the conditions in the bottom of the well, so as to avoid damage and spills to the sample of the formation fluid. . Moreover, the conditions of the sample analysis in the laboratory located on the surface are different from the conditions existing at the bottom of the well, which cause unacceptable and unpredictable variations in the analytical results, and erroneous response products derived from the analysis of the formation fluid.

Advantageously, the present invention obviates the need for a specialized camera to store or analyze the formation fluids. The flow line of a formation-testing tool located at the bottom of the well, through which formation fluids flow during normal operation of the downhole tool, could be advantageously used to isolate fluids from the well. training for the characterization of the fluids at the bottom of the ppzo. Additionally, the same flow line could be used to change fluid conditions for the measurement of additional fluid properties and phase behavior of fluids isolated from the formation.

The foregoing description has been presented solely to illustrate and describe the invention and some examples of its implementation. It is not intended to be exhaustive or to limit the invention to any precise exposed form. Many modifications and variations are possible in view of previously taught.

The preferred aspects were chosen and described with the purpose of better explaining the principles of the invention and its practical applications. The description! The foregoing is intended to enable other persons trained in the art to better utilize the invention in various embodiments and aspects, and with various modifications, as appropriate to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims.

Claims (21)

CLAIMS:

1) A fluid characterization device located at the bottom of a well, comprising: - a fluid analysis module, the fluid analysis module comprises: - a flow line for the fluids that are removed from a formation, to flow through the fluid analysis module, the flow line has a first end for the fluids to enter and a second end for the fluids to leave the module of fluid analysis; - a first selectively operable device and a second selectively operable device, structured and arranged with respect to the flow line, for isolating a quantity of the fluids in a portion of the flow line between the first and second selectively operable device; and - at least one sensor located in the portion of the flow line between the first and the second selectively operable device for measuring the parameters of interest that relate to the fluids in the flow line.

2) The fluid characterization apparatus located at the bottom of the well, according to claim 1, wherein at least one of the first and second selectively operable device comprises a valve.

3) The fluid characterization apparatus located at the bottom of the well, according to claim 1, wherein at least one of the first and second selectively operable device comprises a valve.

4) The fluid characterization apparatus located at the bottom of the well, according to claim 3, wherein the pump is a pumping module of the fluid characterization apparatus located at the bottom of the well.

5) The fluid characterization apparatus located at the bottom of the well, in accordance with claim 1, wherein the fluid analysis module additionally comprises: - a pump unit integrated with the flow line to vary the pressure and the volume of isolated fluids.

6) The fluid characterization apparatus located at the bottom of the well, according to claim 5, wherein the pump unit comprises a syringe-type pump.

7) The fluid characterization device located at the bottom of the well, in accordance! with claim 1, wherein at least one sensor comprises a plurality of sensors.

8) The fluid characterization apparatus located at the bottom of the well, in accordance with claim 1, wherein at least one sensor comprises one or more spectral sensors optimally coupled to the flow line; a fluorescence and gas sensor; a density sensor; a pressure sensor; a temperature sensor; a bubble / gas sensor; a sensor based on an SMMEM; an image producer; a resistivity sensor; a chemical sensor; and a scatter sensor.

9) The fluid characterization device located at the bottom of the well, in accordance; with claim 1, wherein the portion of the flow line for isolating the fluids comprises: a linear bifurcation flow, the first and the second selectively operable device are structured and arranged to isolate the fluids in the line bifurcation flow; and - a circulation line interconnecting a first end of the branch flow line with a second end of the branch flow line, so that the isolated fluids between the first and the second selectively operable device can circulate in a circuit closed formed by the circulation line and the bifurcation flow line; and - the fluid analysis module, which additionally comprises: - a circulation pump for circulating the fluids in the closed circuit of the circulation line and the bifurcation flow line.

10) The fluid characterization apparatus located at the bottom of the well, according to claim 9, wherein at least one sensor comprises one or more density sensors; a pressure sensor; a temperature sensor; a bubbling / gas sensor; a sensor based on an SMMEM; an I producer of images; and a dispersion sensor; wherein at least one sensor measures the parameters of interest that are related to the fluids isolated in the bifurcation flow line, and - the fluid analysis module which additionally comprises: - one or more spectral sensors optically coupled to the flow line; a fluorescence and gas sensor; a chemical sensor; a resistivity sensor, structured and arranged with respect to the flow line, to measure the parameters of interest that are related to the fluids flowing through the flow line.

11) A method for characterizing the fluids of the formation located at the bottom of a well, using a tool located at the bottom of the well that comprises a fluid analysis module that has a flow line for the fluids of the formation that flows through the fluid analysis module, the method comprises of: monitoring at least one first parameter of interest that is related to the formation fluids that flow in the flow line; - when a pre-determined criterion for the first parameter of interest is satisfied, restrict the flow of the fluids of the formation in the flow line, by means of the operation of a first selectively operable device and a second selectively operable device of the fluid analysis module, for isolating the formation fluids in a portion of the flow line of the fluid analysis module, between the first and the second selectively operable device; and - characterizing the fluids isolated by means of the operation of one or more sensors of the flow line between the first and the second selectively operable device.

12) The method of characterization of the fluids of the formation located at the bottom of the well, according to claim 11, wherein the characterization of the isolated fluids includes the determination of one or more properties of the isolated fluids.

13) The method of characterizing the fluids of the formation located at the bottom of the well, according to claim 12, wherein the determination of one or more properties of the fluid comprises of changing the fluid pressure of the isolated fluids, by means of the variation of the volume of the ajislados fluids, before determining one or more properties of the fluids.

14) The method of characterization of the fluids of the formation located at the bottom of the hole, according to claim 13, which additionally will comprise: - monitoring "the time-dependent signals in one or more sensors on the line of flow, to detect the separation by gravity, of the isolated fluids.

15) The method of characterizing the fluids of the formation located at the bottom of the well, in accordance with claim 13, which additionally comprises: - one or more properties of the fluids determined after changing the fluid pressure, It includes one or more fluid compressibilities; beginning of asphaltene precipitation; bubble point; and saturation point.

16) The method of characterization of the fluids of the formation located at the bottom of the well, according to claim 11, which additionally comprises of: - circulating the isolated fluids in a closed circuit of the flow line, while Characterize the isolated fluids.

17) The method of characterizing the fluids of the formation located at the bottom of the well, according to claim 16, wherein: - the characterization of the isolated fluids includes the determination of the behavior of the phase of the isolated fluids, while the fluids are circulated in the closed circuit.

18) The method of characterization of the fluids of the formation located at the bottom of the well, according to claim 17, wherein: - the determination of the behavior of the isolated fluids comprises of monitoring the properties of the sensors that are dependent on time, to detect the separation by gravity of the phases.

19) A tool to characterize the fluids of the formation located in the bottom of the pqzo in a reservoir of an oil field, which comprises of: - a fluid analysis module, the fluid analysis module comprises: - a flow line for fluids removed from a formation, to flow through the fluid analysis module, the flow line has a first end for fluids to enter and a second end for fluids to leave the analysis module of the fluid; - the flow line comprises: - a bifurcation flow line and a circulation line interconnecting a first end to a bifurcation flow line, with a second end of the bifurcation flow line, so that fluids can circulate in the circulation line and in the bifurcation flow line; and - the fluid analysis module, which additionally comprises: - a circulation pump for circulating the fluids in the circulation line and in the bifurcation flow line; - at least one sensor located in the bifurcation flow line, to measure the parameters of interest that are related to the fluids in the bifurcation flow line; and - a first selectively operable device and a second selectively operable device, structured and arranged with respect to the flow line, to isolate a quantity of the fluids in the bifurcation flow line, between the first and the second selectively operable device.

20) The tool for the characterization of the formation fluids, according to claim 19, wherein at least one sensor comprises one or more density sensors; a pressure sensor; a temperature sensori; a bubbling / gas sensor; a sensor based on an SMMEM; a producer of image; and a dispersion sensor; wherein at least one sensor measures the parameters of interest that are related to the fluids isolated in the bifurcation flow line; and - the fluid analysis module, which additionally comprises: - one or more spectral sensors optically coupled to the flow line; a fluorescence and gas sensor; a chemical sensor; and a resistivity sensor; structured and arranged with respect to the flow line, to measure the parameters of interest that are related to the fluids that flow through the flow line.

21) The tool for characterizing the formation fluids, according to claim 20, wherein at least one of the first and second selectively operable device comprises a valve; and the fluid analysis module, which additionally comprises: - an integrated pump with the flow line, to vary the pressure and volume of the isolated fluids. SUMMARY Methods and apparatus for the analysis of the formation fluids located in the bottom of the well, by means of the isolation of the fluids of the formation and / or the hole of the! well, in a pressure and volume control unit that is integrated with a flow line of a fluid analysis module and that determines the fluid characteristics of the isolated fluids. Parameters of interest could be derived for formation fluids in a static state, and undesired formation fluids could be drained and replaced with formation fluids that are suitable for bottomhole characterization or Extraction of the sample from the surface. The fluids isolated from the formation could be circulated in a circuit of the flow line for the characterization of the phase behavior. You can perform a fluid analysis in real time, in or near the conditions! existing at the bottom of the well.